dbutil

type DBOptions struct {
	MaxOpenConns    int
	MaxIdleConns    int
	ConnMaxLifetime time.Duration
}

type Dialect interface {
	// DriverName returns the database/sql registered driver name.
	DriverName() string

	// Placeholder returns the n-th parameter placeholder (1-indexed).
	Placeholder(index int) string

	// CreateMessagesTable returns DDL for the messages table.
	CreateMessagesTable(table string) string

	// CreateAuditTable returns DDL for the audit log table.
	CreateAuditTable(table string) string

	// UpsertMessage returns an upsert statement for the messages table.
	// The statement must accept the same parameter order as the Postgres
	// original: id, correlation_id, channel_id, stage, content,
	// content_size, status, timestamp, duration_ms, metadata.
	UpsertMessage(table string) string

	// InsertAudit returns an INSERT for the audit table.
	// Parameters: timestamp, event, username, details, source_ip.
	InsertAudit(table string) string

	// MigrateColumns returns best-effort ALTER TABLE statements to add
	// columns that may be missing in older schemas.
	MigrateColumns(table string) []string

	// CreateIndexes returns CREATE INDEX statements for the messages table.
	CreateIndexes(table, prefix string) []string

	// CreateAuditIndexes returns CREATE INDEX statements for the audit table.
	CreateAuditIndexes(table, prefix string) []string
}

type MSSQLDialect struct{}

type MySQLDialect struct{}

type PostgresDialect struct{}

type SQLiteDialect struct{}